Researchers with an interest in poverty have long believed that the population that is poor over long periods of time differs in some significant ways from those who are poor over shorter periods. Indeed, data from the University of Michigan’s Panel Study of Income Dynamics (PSID) make it clear that the very long-term poor—those with incomes below the poverty threshold over a period of eight or more years—are quite different in several dimensions from those who are counted as poor in our official poverty statistics, which are based on annual income as measured in the Current Population Survey (CPS). Among other findings, the long-term poor are more likely to be in female-headed families, are more likely to be elderly, and are more likely to be non-white than are those who are poor on the basis of an annual income measure.